Nano

BENEFITS TO YOU

Sealing a surface with nanotechnology means applying nano-structures onto the surface – these treated surfaces become super-hydrophobic and thereby water-rejecting – which means easier and faster cleaning for you and improved protection for the surface. It takes longer for the dirt to bond to the surface and it canTMt burn itself into the surface at high temperatures. Although all these advantages do not mean that the surface needs no further cleaning at all. The surfaces can be cleaned much more easily and faster than before # you save up to 80% of your time with our products. After the appropriate nano-substance has been applied to the cleaned surface the nano-particles organize themselves and form the desired structure. We offer our customers coatings for almost every known technical surface, such as metals, glass, textiles, plastics etc.

A nano-coating is can be applied for example in the bathroom, as anti-finger print coating on screens, as a self-cleaning house exterior or as paint protection for cars.

THE LOTUS FLOWER EFFECT

The Lotus effect refers to the very high water repellency (superhydrophobicity) exhibited by the leaves of the lotus flower. Dirt particles are picked up by water droplets due to a complex micro- and nanoscopic architecture of the surface which enables minimization of adhesion.

This effect can easily be demonstrated in many other plants as for example tropaeolum, cane, or columbine, and on the wings of certain insects.

The phenomenon was first studied by Dettre and Johnson in 1964 using rough hydrophobic surfaces. Their work developed a theoretical model based on experiments with glass beads coated with paraffin or PTFE telomer. The self-cleaning property of superhydrophobic micro-nanostructured surfaces was discovered in the 1970s and has been applied since the 1990s in biomimetic technical products. Perfluoroalkyl superhydrophobic materials were developed in the mid 1990’s for use with chemical and biological fluids.

Due to their high surface tension water droplets tend to minimize their surface trying to achieve a spherical shape. On contact with a surface, adhesion forces result in wetting of the surface:either complete or incomplete wetting may occur depending on the structure of the surface and the fluid tension of the droplet. The cause of self-cleaning properties is the hydrophobic water-repellent double structure of the surface. This enables the contact area and the adhesion force between surface and droplet to be significantly reduced resulting in a self-cleaning process. This hierarchical double structure is formed out of a characteristic epidermis (its outermost layer called the cuticle) and the covering waxes.The epidermis of the lotus plant possesses papillae with 10 to 20 # in height and 10 to 15 # n width on which the so-called epicuticular waxes are imposed. These superimposed waxes are hydrophobic and form the second layer of the double structure.

The hydrophobicity of a surface is determined by the contact angle. The higher the contact angle the higher the hydrophobicity of a surface. Surfaces with a contact angle< 90 # are referred to as hydrophilic and those with an angle>90 # as hydrophobic. Some plants show contact angles up to 160 # and are called super-hydrophobic meaning that only 2-3% of a drop’s surface is in contact. Plants with a double structured surface like the lotus can reach a contact angle of 170 # whereas a droplet ae TM s actual contact area is only 0.6%. All this leads to a self-cleaning effect.

Dirt particles with an extremely reduced contact area are picked up by water droplets and are thus easily cleaned off the surface. If a water droplet rolls across such a contaminated surface the adhesion between the dirt particle, irrespective its chemistry, and the droplet is higher than between the particle and the surface. As this self-cleaning effect is based on the high surface tension of water it does not work with organic solvents. Therefore, the lotus-effect is no protection against graffiti.

This effect is of a great importance for plants, not for keeping them clean but as a protection against pathogens like fungi or algae growth. This also applies to animals like butterflies, dragonflies and other insects not able to cleanse all their body parts. Another positive effect of self-cleaning is the prevention of contamination of the area of a plant surface exposed to light resulting in a reduced photosynthesis.